Photographic-plate-centering device



Jan. 6,l 1925. 1,521,633

A. T. KOPPE PHOTOGRAPH-IC PLATE CENTERING DEVICE Filed Aug. 25, 1922 5Sheets-Sheet l I N VEN TOR.

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Jan. 6, 1925- 1,521,633 i A. T. KoPPE PHOTOGAPHIC PLATE CENTERING DEVICE5 Sheets-Sheet 2 Filed Aug. 25, 1922 sa@ f ff Z2 545,67

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Jan. 6, 1925. 1,521,633

A. T. KoPPE PHOTOGRAPHIC PLATE CENTERING DEVICE Filed Aug. 23, 1922 3Sheets-Sheet 3 ffy' 2 ATTORNEY.

Patented Jan. 6., 1925.

UNITED STATES PATENT OFFICE.

ALEXANDER T. IOPPE, F CHICAGO, ILLINOIS, \ASSIGNOR T0 OFFSETDIRECTOPLATE COMPANY, 0F CHICAGO, ILLINOIS, A CORPORATION 0F ILLINOIS.

PHOTOGRAPHIC-PLATE-CENTEBING DEVICE.

Appiiuon ma August 2s, 1922. serial No. ssa'zsl..

To all whom it may concern:

Be it known that I, ALEXANDER T. lorrn,

a citizen of the United States, residmg at Chicago, in the county ofCook and State of 6 Illinois, have invented certain new and usefulImprovements in Photographic-Plate- Centering Devices, of which thefollowing 1s a specification.

K The invention relates to photographlc l0 plate centerin devices, andhas for its object to provi e a device of this character, which ismounted in the plate holder of the camera, and constructed in such amanner whereby plates may be accurately centered, removed and replacedif so desired, and whereby successive plates, for instance of the typeused in color photography may be accurately centered, even if their sizevaries. It has been found that photographlc plates vary slightly, indimensions, which variation prevents proper registratlon when the platesare placed in a press plate machine, such for instance as set forth 1nmy ap lication for patent iled th day of June 19 2, Serial No. 57 2,054.

A further object is to mount the plate centering device in the lateholder of the camera, and on which evice the plate 1s supported. Also toprovide a vertically sl 1d 30 able member in the plate holder forengagln and holding the upper end of the Plate an to rovide spacednotches for receiving the en s of the supporting bar of the platecentering device, whereby the centering device as a whole may beadjusted upwardly or downwardly for placing the plate in registrationwith the camera lens.

A further object is to provide a photographic plate centering devicecomprising a bar on which a plate is slidably supported,

ali ed apertured bars slidably mounted in a c annel of the supportingbar, any of the apertures of which receiye and hol d plate engagingmembers, the' slidable bars having 4 their apertures correspondinglynumbered whereby the plate engaging members may be removed and replacedwith accuracy. The slidable bars are adjustable inward y and outwardlysimultaneously by means of '50 right and left handed -threaded shafts,

which are threaded into the bars, and which are simultaneously rotatedthrough a -wor1n and worm gear connection. The simultaneous movement ofthe slidable bars forming 5 means for centering the plate in relation tothe lens center and the subject carried by the copy board irrespectiveof the variation in the width of the plate.

With the above and other objects in view the invention resides in thecombination and and arran ement of partsv as hereinafter set forth, sown in the drawings, described and claimed, it being understood thatchanges in the precise embodiment of the invention may be made withinthe scope of what is claimed without departing from' the spirit of theinvention.

In the drawings F i ure 1 is a side elevation of a conventiona form ofcamera and the plate holder, showing the copy board in front of thecamera.

Figure 2 is a rear view of the plate holder showing the cover in openposition and the plate centering device in the holder.

' Figure 3 is an enlarged rear elevation of the plate centering device.

Figure 4 is a vertical transverse sectional view through the platecentering device taken on line 4-4 of Figure 3.

Figure 5 is a vertical transverse sectional view through the platecentering device taken on line 5--5 of Figure 3.

Figure 6 is a view of the inner end of one of the locking sleeves, and aportion of one of the slide bars.

Figure 7 is a front elevation of the copy board showing a copy thereon.

Fi re 8 is a rear elevation of the centering evice showing a doubleplate and in dotted lines the shifted position of the plate and plateengaging members.

Figure 9 is a rear elevation of the plate, showing a color separatingscreen and a mask in connection therewith, the plate being a double one.

Referring to the drawings, the numeral 1 designates a conventional formof camera and 2 the plate holder carried thereby. Disposed in front ofthe camera is a copy board 3 on which is disposed a copy 4 having thecolored subject 5 thereon. The subject 5, for purposes of illustration,is shown as comprising concentric rings 6 and 7, and a central roundportion 8. It has been found in colored photography, wherein subjectsare placed on dry plates forming negatives, and then placed in an offsetpress plate machine of the type set forth in the application mentionedabove, and reproduced on a sensitized plate, the variations incident tothe dimensions of the negatives will at times prevent perfectregistration. To obviate this diiculty and center the subject on thephotographic dry late, no matter what the variation of wi th in theplate or successive plates may be, the plate holder 2 is provided with aplate centering dev1ce`9, which centering device comprises ahorizontally disposed supporting bar 10, the ends of which are providedwith ton es 11, which are received in recesses 12, o the vertical sidebars 13 of the plate holder 2. It will be seen that the horizontallydisposed bar may be adjusted to various sitions in a vertical planewithin the late older 2 according to the position of t e lens 14 of thecamera. The side bars 13 of the plate holder are provided withvertically disposed channels 15 in their inner faces, in which channelsare slidably mounted the ends 16 of the horizontally disposed lateholding bar 17. The bar 17 en t e upper end of the dry plate 18, an w enthe dry plate is resting in the groove 19 of the bar 2O carried by theupper side j of the horizontally disposed bar 10, the dry plate-is heldin a vertical lane.

Slidab y mounted in a horizontally. disposed channel 21 of thesupporting bar 10 at opposite sides of the center of the bar and thecenter of the lens 14 are horizontally aligned slidable gage bars 22,which bars are provided with a plurality of spaced apertures 23, whichapertures are equally spaced from each other, and the correspondingapertures at each side of the center of the bar 10 are correspondinglynumbered as clearly shown in Figure 3. Detachably secured to theslidable bars 22 are L-shaped members 24, the arms 25 of which overliethe channel 19 of the bar 20, and are adapted to engage the oppositesides26l of the dry plate 18, when the bars 22 are moved towards eachother for centering the dry late in relation to the center of the lens14 o the camera. The arms 26 of the members 24 Y extend downwardly andengage the outer faces of the bars 22 and are referably provided withilanges 27 whic engage in a channel 28 of the bar 10. The members 24 areremovable from the bars 22, however they ma be securel held and securedto the bars 22 gy means o the set screws 29, which are threaded throughsleeves 30 carried by the arms 26 of the members 24. The inner ends ofthe set screws 29 are tapered as shown at 31, and engage within thesplit ends 32 of the sleeves 30, and spread the same in such a mannerthat they will frictionally engage the walls of the apertures 23,thereby securely holding the members 24 on the bars 22 and at the sametime al-l lowin the members 24 to be easily removed when it is desiredto adjust the members 24 in re ration with other apertures 23. The memrs 24 are placed in registration with corresponding apertures of thebars 22 as shown in Figure 3, thereby placing the plate engaging arms 25adjacent the sides 26'* of the dry plate, but suiciently far eno htherefrom to accommodate the centeringudevice tovmaximum variations ofwidths vof plates 18. Secured centrally of the bar 10, and centrally inrelation te the lens 14, by means of screws 33 is a bracket 34. Thebracket 34 is provided with a bearing 35, in which is rotatably mounteda transversal dispgsed shaft 36, the inner end of said shafyt 36 inrotatably mounted in a bearing 37 of the ar 10, and is provided with aworm 38. The worm 38 meshes with a worm 39 carried by a sleeve 40, whichis rotatably mounted in the bracket 34, and t: within the channel 21 ofthe bar 10. Secured to the outer ends of the sleeve 40, by means of pins41 are axially aligned shafts 42, the outer ends of which are threadedat 43 into the end s of the slidable bars 22, and are jrovided withright and left hand thread as c early shown in Figure 3. It will be seen that when the sleeve 40 is rotated in either direction, the shafts42 will be simultaneously rotated and consequently the slidable bars 22will be simultaneously moved inwardly or outwardly as desired. en thebars 22 are moved inwardly at the same rate of speed, it is obvious thatthe late engag. ing arms 25 will move inwardly the same distance, andwill engage the sides 26 of the plate 18 and center the plate inrelation to the center of the lens 14. It will also be seen thatsucceiveilates, even though they vary in width, inci ent to manufacture,will be accurately centered. The shaft 36 is provided with a fingerengaging wheel 44,l by means of which the worm 38 may be easily turnedfor moving the slidable bars 22 inwardly for eenterin the plate 18, oroutwardly when the p ate is being removed. By providing a plurality of art'ures 23 in the slide bars 22, it is obvious t at the device may beadjusted for use in connection with various sizes of plates, however byreferring to Figure 8, it will be seen that the device is adjusted foruse in connection with a lar plate 18, over which a dummy layout 45 isdisposed. In this form after the ortion of the plate 18, which is dis inregistration with the lens 14, is utilized, the plate 18 may be shiftedto the dotted line position shown in Figure 8, and the portion 18" ofthe plate 18l positioned and centered in relation to the lens 14.

Referring to Figure 9, the double or large dry plate 18 is shown with acolor separating screen 46 and a mask 47.

From the above it will be seen that a plate centering device is providedfor camera plate holders wherein successive plates may be lll easily andquickly positioned and centered irrespective of the width of plates. Itwill also be seen that the device is entirely housed within the plateholder, and that the same may be adjusted for plates of differentheights as well as widths, and consequently successive plates may bemade, the objects on which will register when used in connection with anoset press plate machine,particu larly of the character set forth above.

The invention having been set forth what is claimed as new and usefulis 1. The combination with a plate holder, of a plate centering devicecarried by said holder, said centering device comprising a platesupporting bar, slidable apertured bars carried by the plate supportingbar, adjustable plate engaging members carried by the slidable aperturedbars, means whereby the plate engaging members may be secured to theslidable bars in registration with any of the. apertures, and meanswhereby said slidable bars may be moved towards and away from eachother.

2. The combination with a plate holder, of a plate centering devicecarried thereby, said plate centering` device comprising a platesupporting bar, slidable bars carried by said bar, plate engaging stopsadjustably carried by. the slidable' bar and adapted to engage theopposite edges of a plate, and means carried by the plate supporting barfor simultaneously moving the slidable bars towards and away from eachother.

3. The combination with a plate holder, of a plate centering devicecarried thereby, said plate centering device comprising a platesupporting bar, inwardly and outwardly adjustable apertured bars carriedby the supporting bar, plate engaging members carried by the adjustablebars, means for attaching the plate engaging members to the adjustablebars in registration with any of the apertures therein, and meanscarried by the plate supporting bar for moving the apertured barsimultaneously outwardly and inwardly.

4. The combination with a camera plate holder, of a plate supporting andcentering device carried by said plate holder, said device comprising ahorizontally disposed bar, aligned slidable apertured bars carried bythe horizontally disposed bars, plate engaging members carried by thealigned apertured bars, means whereby said plate engaging members may beattached at various positions on the apertured bars, right and lefthanded screws threaded into the adjacent ends of the apertured bars, andmeans for simultaneously rotating said right and left handed threadedscrews.

5. The combination with a plate holder, of a plate centering devicecarried by said holder, said centering device comprising a platesupporting bar, alined endwise slidable bars carried by the platesupporting bar, plate engaging members adjustable on said slidable barsadapted to engage the opposite edges of plates of various sizes by themovement of the slidable bars, and means for simultaneously moving saidslidable bars towards and away from each other.

In testimony whereof I affix my signature.

ALEXANDER T. KOPPE.

